The STD932  (P/N 152-0373-00) is a 4.7 mA, 50 pF tunnel diode.

The TD716 appears to be equivalent.

Some instruments using part STD932

Instrument Manufacturer Class Model Description Introduced
115 Tektronix Pulse generator 115 Pulse generator 1968
1S2 Tektronix Plug-in 1S2 Sampling system/TDR 1967
31 Tektronix Computer 31 Programmable desktop calculators 1973
564B Tektronix Oscilloscope 564B Split-screen storage scope 1969